I tested the export dialog and selected the pcx format for export.
To test the RLE compression I recognize, that the RLE compression produce bigger files!
Is it correct? I though a picture compression reduce the filesize and do not increase it.

The upper picture shows the picture without RLE compression and the lower picture with RLE compression.

I tested the export dialog and selected the pcx format for export.
To test the RLE compression I recognize, that the RLE compression produce bigger files!
Is it correct? I though a picture compression reduce the filesize and do not increase it.

I think the answer is simply that different types of compression are best suited to different types of image: colour mode (colour, grayscale or black and white) and different types of content: (photograph or line drawing, for example).

In this case RLE compression isn't suited to the complexity of your photo, but it could be very effective for a line drawing.